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iOS Build a Simple iPhone App with Swift Getting Started with iOS Development Swift Recap Part 2

Miguel Eduardo Saballa
Miguel Eduardo Saballa
1,061 Points
Posted by Miguel Eduardo Saballa
Miguel Eduardo Saballa
1,061 Points

Hi, I am stuck in this challenge. Would be great to get some tips. Thanks.

// code obviously doesn't work :D

class Robot: Machine { override init() { super.init() }

override func move(_ direction: String) {
    switch move {
    case "Up":
        self.location = Point(x: 0, y: 1)
    case "Down":
        self.location = Point(x: 0, y: -1)
    case "Left":
        self.location = Point(x: -1, y: 0)
    case "Right":
        self.location = Point(x: 1, y: 0)
    default: break
    }
}
robots.swift 
class Point {
  var x: Int
  var y: Int

  init(x: Int, y: Int) {
    self.x = x
    self.y = y
  }
}

class Machine {
  var location: Point

  init() {
    self.location = Point(x: 0, y: 0)
  }

  func move(_ direction: String) {
    print("Do nothing! I am a machine!")
  }
}

// Enter your code below

2 Answers

Jeff McDivitt
Jeff McDivitt
23,970 Points
Jeff McDivitt
Jeff McDivitt
23,970 Points

Hi Miguel - The first error is that you are not switching on (direction) instead you have move. The next error is on your return statements for the cases. The correct code is below

class Point {
    var x: Int
    var y: Int

    init(x: Int, y: Int) {
        self.x = x
        self.y = y
    }
}

class Machine {
    var location: Point

    init() {
        self.location = Point(x: 0, y: 0)
    }

    func move(_ direction: String) {
        print("Do nothing! I'm a machine!")
    }
}

class Robot: Machine {

    override func move(_ direction: String) {
        switch direction {
        case "Up":
            location.y += 1
        case "Down":
            location.y -= 1
        case "Left":
            location.x -= 1
        case "Right":
            location.x += 1
        default:
            break
        }
    }
}